Following can be adapted to whatever, this is just a base template for some possibilities, from crack to something more serious whatever floats boats.
1) Martin decides to test out a spell
a) keep out intruders by sending them to different dimensions
b) send intruders to demon hotspots
c) tests out a time spell of some sort
2) Something (curious teammates, distractions, explosions, general chaos) breaks his concentration or (preferably) panics him, causing the spell to be reversed or inverted or such
3) Results:
a) Instead of intruders sent to different dimensions, all the teammates in the building including Martin get sent to said dimensions. (This can result in literally anything from vampire clowns (thanks Marlow), zombie pirranhas, fighting evil versions of self/teammates, and pretty much whatever someone wants. Magic plus dimension hopping can explain a lot)
b) Instead demons get transported into HQ
c) TBolts are sent back in time (historical fun) or into the future (distant or recent like seeing future selves)
4) Team must fight their way either out of where they are (a and c) to give Martin some time to set up spells to send them back (can take multiple tries so more than one dimension/time period can be used) or must rid the HQ of their demon pests.
5) Thunderbolts get back (if it's an ongoing/constant spell he started then he manages to stop the spell)
6) Martin decides that maybe the living room isn't a good place to cast/test out spells.
And they all lived not-so-sanely ever after.
Note: If we go for the time travel plot I don't think Martin has the skill or knowledge at this point to get them accurately back to the right time. This could result in a few time jumps closer and I might need to get the future version of him to show up at the end and fish them all out and back to the right time. (He probably won't see his future self though, the others might).
