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The z = 6.6 Lyman-$\alpha$ emitter 'CR7' has been claimed to have aPopulation III-like stellar population, or alternatively, be a candidate DirectCollapse Black Hole (DCBH). In this paper we investigate the evidence for theseexotic scenarios using recently available, deeper, optical, near-infrared andmid-infrared imaging. We find strong Spitzer/IRAC detections for the maincomponent of CR7 at 3.6 and 4.5 microns, and show that it has a blue colour([3.6] - [4.5] $= -1.2\pm 0.3$). This colour cannot be reproduced by currentPop. III or pristine DCBH models. Instead, the results suggest that the [3.6]band is contaminated by the [OIII]4959,5007 emission line with an impliedrest-frame equivalent width of EW_0 (H$\beta$ + [OIII]) $\gtrsim 2000$\AA.Furthermore, we find that new near-infrared data from the UltraVISTA surveysupports a weaker He II 1640 emission line than previously measured, with EW_0$= 40 \pm 30$\AA. For the fainter components of CR7 visible in Hubble SpaceTelescope imaging, we find no evidence that they are particularly red aspreviously claimed, and show that the derived masses and ages are considerablyuncertain. In light of the likely detection of strong [OIII] emission in CR7 wediscuss other more standard interpretations of the system that are consistentwith the data. We find that a low-mass, narrow-line AGN can reproduce theobserved features of CR7, including the lack of radio and X-ray detections.Alternatively, a young, low-metallicity (~1/200 solar) starburst, modelledincluding binary stellar pathways, can reproduce the inferred strength of theHe II line and simultaneously the strength of the observed [OIII] emission, butonly if the gas shows super-solar $\alpha$-element abundances (O/Fe ~ 5 O/Fesolar).

No evidence for Population III stars or a Direct Collapse Black Hole in the z = 6.6 Lyman-$\alpha$ emitter 'CR7'