ORIGINAL AIRDATE: February 26th, 1990 ---
A submarine cloaking device is stolen, coincidentally the inventor's dating a shady submarine salesman.
MISSION: The ERMA cloaking device was intended to hide police from drug dealers, but the opposite may be the case now that the device has been stolen. MacGyver must infiltrate the den of thieves as new crowd favorite character Dexter the nerd.
This week's highlights include:

Cloaking device (Technology)

A cloaking device is a theoretical or fictional stealth technology that can cause objects, such as spaceships or individuals, to be partially or wholly invisible to parts of the electromagnetic (EM) spectrum. However, over the entire spectrum, a cloaked object scatters more than an uncloaked object.

Check out the article on wikipedia: https://en.wikipedia.org/wiki/Cloaking_device.

Watch S5E16: "Deep Cover" on CBS's website or check the alternative streamability of this episode here.