Nature & Geometry, a small exhibit of newworks by artists Michael Marshall, David Peterson and Brendan Murphy, explores the relationship between humans and their connection to the environment in the modern world. Noon to 6 p.m.; Through Aug. 30. Free. Definition Gallery, 1800 Fleet St., Baltimore. 410-342-0577.
WHO?S IN TOWN
Since 1971, Canadian hard-rock band Frank Marino & Mahogany Rush has lit up stadiums with great progressive, psychedelic rock. Let?s hope that tonight, a nostalgic set will be chock-full of oldies and fan favorites. 8 p.m. $35. Rams Head On Stage, 33 West, Annapolis.
MUSIC
Fertile Ground and Olu Butterfly host Eden?s Lounge?s weekly Organic Soul open-mic and spoken-word event. 8 p.m. Free. Eden?s Lounge, 15 W. Eager St., Baltimore. 410-244-0405.
Local rock cats Rob Hughes & the Heaters play. 9 p.m. to 1 a.m. Cat?s Eye Pub, 1730 Thames St., Baltimore. 410-276-9866.
Lots of great guitarists and singers get their start at open-mic nights. You can, too! Get your groove on at tonight?s weekly event with Jordan Benson. 7 p.m. Free. Judge?s Bench Pub, 8385 Main St., Ellicott City. 410-465-3497.
EXHIBIT
Philadelphia Meets Baltimore: Conceptions and Perceptions is an exhibition that concentrates on the “new” abstraction taking place in paintings, fibers and sculptures from these featured cities. Philadelphia-area artists Neil Anderson, Charles Burwell, Alice Oh, Tim McFarlane and Thomas Vance complement Baltimore-area artists Seth Adelsberger, Karin Birch, Ellen Burchenal, Lawrence Cromwell, Kay Hwang, Michelle Kong and Michael Weiss. 11 a.m. to 4 p.m. Free. Through Aug. 2. Towson University, Center for the Arts Gallery at Cross Campus Drive and Osler Boulevard. 410-704-2787.
LECTURE
Recently separated and looking to meet someone new? Friends of Mercy Church?s “Single Again Friends” discussion tonight focuses on the topic of enjoying a solo summer. The monthly event is ideal for the spiritually minded (of all religious backgrounds). 7 to 9 p.m. $2 donation. Hiss United Methodist Church. 8700 Harford Road, Harford. 410-893-4584.
KIDS
Diane from the Baltimore Museum of Industry shares her expertise at creating multimedia pictures of summertime idylls at today?s “Kids Beach Scene/Landscape Art Class.” 4 p.m. Free; preregistration required. Whole Foods Market, 1330 Smith Ave., Baltimore. 410-532-6700.
EVENTS
Take a load off while sharpening your sleuthing skills. The Ottobar hosts “Grunged Mystery,” featuring Whodunnit Players, tonight. 7 p.m. $2.50 to $5. The Ottobar, 2549 N. Howard St., Baltimore. 410-662-0069.
FILM
Head to the Baltimore Hostel for a screening of “Tin Men”: Richard Dreyfuss and Danny DeVito star as two competing salesmen in 1960s Baltimore. 8 p.m. Free. Baltimore Hostel, 17 W. Mulberry St., Baltimore. 410-576-8880.
